1. Field of the Invention
The present disclosure relates to a bearing system and method, in particular, in non-contact systems.
2. Discussion of Background Information
There are three key metrics for measuring the utility of a magnetic bearing system, also called a levitation system: lift-to-drag ratio, lift-to-system mass ratio, and levitation length. The lift-to-drag ratio measures the vertical force created by the system compared to the frictional deceleration force parallel to the direction of motion. For the lift-to-system mass ratio, the weight of the system is measured against its ability to create a vertical force. If the levitation system comprises the majority of the system's weight, then the levitation system's utility may be severely limited. The levitation length measures what length of levitation system is necessary for a nominal system's mass. For example, if the levitation length exceeds the length of the vehicle, then the entire system may be impractical.
One exemplary use for a magnetic bearing system may be in an ultra-high speed, high efficiency transportation system that may utilize a low pressure environment in order to reduce drag on a vehicle at high operating speeds, thus providing the dual benefit of allowing greater speed potential and lowering the energy costs associated with overcoming drag forces. These systems may use a near vacuum within a tubular structure in which the vehicle moves. These systems may utilize any number of acceleration systems to achieve the desired high speed for the vehicle, including electromagnetic propulsion. Due to the scale of the project, tremendous forces are required to accelerate the vehicle to the operating speed.
Due to the unprecedented nature of the sustained, ultra-high speed configuration of the system, the vehicle needs to utilize a carriage that can withstand the frictional demands of the high speed and high use. Conventional carriage systems, such as wheels, will not provide the durability or efficiency for the transportation system to be operable, let alone useful.
Many passive levitation systems suffer from poor lift-to-drag ratio, poor lift-to-magnet mass ratio, sub-optimal stiffness in both transverse directions, poor stability characteristics, and/or low ride height. However, these problems are not limited to passive maglev, and have been found to affect active maglev systems as well. These problems exist because of the limitations of permanent and electro-magnets and/or control circuits, the necessity to reduce track capital expenses even at the cost of higher operational expenses, and limited use of automation in manufacture. Both track- and vehicle-side systems to address these issues are often expensive, difficult to manufacture, ineffective, or all three.